Scheelite

scheelite

wulfenite

hubnerite

ferberite

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Formula: Ca(WO4) Tungstate
Specific gravity: 5.9 - 6.1
Hardness: 4½ to 5
Streak: White
Colour: Tan, golden-yellow, colourless, white, greenish, dark brown, etc.; colourless in transmitted light May be compositionally colour zoned.
Solubility: Slightly soluble in hydrochloric acid
Common impurities: Mo,Nb,Ta
Environments:

Plutonic igneous environments
Pegmatites
Placer deposits
Metamorphic environments (common)
Hydrothermal environments

Scheelite is a primary mineral found in granite pegmatites and also a secondary mineral in contact metamorphic deposits and in the oxidation zone of hypothermal (high temperature) hydrothermal veins in granitic rocks and in alluvial deposits.
In contact metamorphic environments it may be associated with molybdenite. In hydrothermal veins it is associated with apatite, arsenopyrite, cassiterite, fluorite, topaz and hübnerite-ferberite.

Localities

The Two Mile and Three Mile deposits, Paddy's River, Paddys River District, Australian Capital Territory, Australia, are skarn deposits at the contact between granodiorite and volcanic rocks. Scheelite is a primary oxide that occurs at the Two Mile deposit in massive and granular forms in magnetite and amphibole skarn. Rare green plates of scheelite with langite have been observed in magnetite (AJM 22.1.38).

The Lin Fa Shan deposit, Tsuen Wan District, New Territories, Hong Kong, China, is located in a remote area of the Tai Mo Shan Country Park, on a steep west facing slope of Lin Fa Shan, just above the abandoned village of Sheung Tong. The surrounding hillsides are covered with shallow excavations, representing past searches for wolframite, the natural ore of tungsten. The abandoned workings are extremely dangerous with unsupported tunnels, open shafts and no maintenance since their closures in 1957; the workings should not be entered (http://industrialhistoryhk.org/lin-shan).
Scheelite occurs in small amounts with wolframite in the hydrothermal ore deposit. Lin Fa Shan is the only locality in Hong Kong where scheelite is found with wolframite (Hong Kong Minerals (1991). Peng, C J. Hong Kong Urban Council).

At Trumbull, Fairfield county, Connecticut, USA, wulfenite pseudomorphs after scheelite have been found (KL p217).

At Long Hill, Haddam, Middlesex county, Connecticut, USA, ferberite pseudomorphs after scheelite have been found (KL p215).

At the Gold Hill District, Deep Creek Mountains, Tooele county, Utah, USA, cuprotungstite pseudomorphs after scheelite have been found (KL p218).

Alteration

Scheelite may form as an alteration product of ferberite (AJM 18.2.26).

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